Eliza Jane Martin - b. 1829 Hancock Co.

Searching for information on my g-g-grandmother, Eliza Jane Martin, her family and ancestors. She was born 8/4/1829 in Hancock Co. Indiana. She married Isaiah Thomas in 1847 in Iowa and they traveled by wagon train to Sonoma Co., California. They had 12 children, with 11 surviving to adulthood. Would appreciate any suggestions that might produce more information.